TWI766997B - Vacuum drying device and vacuum drying method - Google Patents

Abstract

Provide a time until the vacuum drying of the substrate is completed Shorter vacuum drying device.

The vacuum drying device (1) is in a reduced pressure state, so that the For drying the solvent in the organic material film coated on the surface of the substrate (W), the vacuum drying device is provided with: a chamber (10) for accommodating the substrate; and a plurality of exhaust pipes (30) for connecting the chambers The space in the chamber (10) and the exhaust device (P) for exhausting the inside of the chamber (10), a plurality of exhaust pipes (30) are respectively provided with a switch to freely close the exhaust pipe (30). APC valve (31), a plurality of exhaust pipes (30), including: an exhaust pipe (30) with a solvent trapping part, downstream of the APC valve (31), a trapping slave substrate (W) is provided The solvent trapping part (32) of the solvent in the vaporized solution; and the exhaust pipe (30) without the solvent trapping part are not provided with the solvent trapping part (21).

Description

Vacuum drying device and vacuum drying method

The present invention relates to a vacuum drying apparatus for drying a solvent in an organic material film coated on a surface of a substrate in a reduced pressure state.

Conventionally, Organic Light Emitting Diode (OLED: Organic Light Emitting Diode), which is a light emitting diode utilizing light emission of organic EL (Electroluminescence), has been known. The organic EL display using this organic light emitting diode has the advantages of being thin, lightweight, and low in power consumption, as well as being excellent in response speed, viewing angle, and contrast. ) has attracted much attention.

The organic light-emitting diode has a structure in which an organic EL layer is interposed between an anode and a cathode on a substrate. The organic EL layer is formed by laminating, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer in this order from the anode side. When forming each of these organic EL layers (particularly, the hole injection layer, the hole transport layer, and the light emitting layer), a method of discharging droplets of an organic material onto a substrate by an inkjet method can be used, for example.

The organic material discharged onto the substrate by the ink jet method contains a large amount of solvent. Therefore, for the purpose of removing the solvent, a drying treatment under reduced pressure for drying the solvent is performed in a reduced pressure state.

A vacuum drying apparatus for performing a vacuum drying process is provided with: a processing container that accommodates a substrate to be dried under reduced pressure and can be evacuated; and an exhaust pipe, one end of which is connected to the processing container, and the other end is provided with It is an exhaust device, and the inside of the processing container is exhausted by the exhaust device (refer to Patent Documents 1 and 2).

The reduced-pressure drying apparatus of Patent Document 1 is intended to rapidly dry the substrate, etc., and the exhaust pipe is provided with a solvent collecting part for collecting the solvent volatilized from the organic material film on the substrate. If the substrate is dried under reduced pressure When it is completed, the valve provided between the solvent trapping part and the processing container is closed, the inside of the processing container is returned to the atmospheric pressure, and the substrate is unloaded from the processing container.

In addition, in the vacuum drying apparatus of Patent Document 2, in order to efficiently remove the solvent in the processing container in a short time, the above-mentioned solvent trapping part is provided in the processing container, and an ultraviolet irradiation part is provided for the processing container. This vacuum drying apparatus decomposes by irradiating ultraviolet rays from the ultraviolet irradiation part to the solvent trapping part so as to easily volatilize the organic compounds contained in the solvent trapped by the solvent trapping part.

[Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2005-85814

[Patent Document 2] Japanese Patent Laid-Open No. 2014-238194

[Problems to be Solved by the Invention]

However, it is sometimes required that the time until the drying of the substrate under reduced pressure is completed, in other words, the time until the pressure in the processing chamber becomes below a predetermined value and no problem occurs even if the pressure in the processing chamber returns to the atmosphere (takt time) It is shorter than the vacuum drying apparatus of Patent Documents 1 and 2.

The present invention has been made in view of this point, and an object of the present invention is to provide a reduced-pressure drying apparatus with a short time until the reduced-pressure drying of the substrate is completed. [means to solve the problem]

In order to achieve the aforementioned object, the present invention relates to a vacuum drying device, which dries the solvent in the organic material film coated on the surface of the substrate under reduced pressure. The vacuum drying device is characterized by: It is provided with: a chamber for accommodating the substrate; and a plurality of exhaust paths connecting the space in the chamber and an exhaust device for exhausting the inside of the chamber, and the plurality of exhaust paths are respectively provided with switches and can be closed freely. The closing member of the exhaust passage, the plurality of exhaust passages, includes an exhaust passage having a solvent trapping portion, and downstream of the closing member, is provided with an exhaust passage that collects the solution vaporized from the substrate. The solvent collection part of the solvent and the exhaust path without the solvent collection part are not provided with the solvent collection part.

The end portion on the chamber side of the exhaust path with the solvent trap portion is farther from the chamber accommodated in the chamber than the end portion on the chamber side of the exhaust path without the solvent trap portion. The corners of the aforementioned substrates are preferred.

Preferably, a temperature variable mechanism is provided for cooling and/or heating the solvent trapping portion.

Preferably, between the solvent trapping portion and the closing member, a gas supply portion for supplying a gas that promotes the vaporization of the solvent trapped by the solvent trapping portion is provided.

According to another aspect of the present invention, there is provided a method of drying under reduced pressure using a vacuum drying device that, under reduced pressure, causes a solvent in an organic material film to be coated on the surface of a substrate to be Drying, the vacuum drying method is characterized in that the vacuum drying device is provided with: a chamber for accommodating the substrate; and a plurality of exhaust paths for connecting the space in the chamber and exhausting the chamber The exhaust device of the invention, the plurality of exhaust paths are respectively provided with a closing member that can open and close the exhaust path, and the plurality of exhaust paths include: an exhaust path with a solvent trapping portion, and the exhaust path has a solvent trap. On the downstream side of the sealing member, a solvent trapping part for trapping the solvent in the solution vaporized from the substrate is provided; and an exhaust path without a solvent trapping part is provided without the solvent trapping part, and the drying under reduced pressure The method includes: a substrate drying step of opening the closing member for at least the exhaust path having the solvent trap part among the plurality of exhaust paths; and a chamber drying step, in which the substrate drying step Then, the closing member is closed for the exhaust passage with the solvent trapping portion among the plurality of exhaust passages, and the closing member is opened for the exhaust passage without the solvent trapping portion.

Preferably, the substrate drying step includes a step of cooling the solvent trapping portion.

Preferably, the chamber drying step includes a step of heating the solvent trapping part.

Preferably, the chamber drying step includes the following step: from a gas supply part provided between the closing member and the solvent trapping part, a gas supplying part for promoting the trapping of the solvent by the solvent trapping part is supplied. vaporized gas.

The end portion on the chamber side of the exhaust path with the solvent trap portion is farther from the chamber accommodated in the chamber than the end portion on the chamber side of the exhaust path without the solvent trap portion. Preferably, the corner portion of the substrate, the substrate drying step, preferably includes the following step: for the exhaust path having the solvent trap portion among the plurality of exhaust paths, the closing member is in an open state, which After that, for all of the plurality of exhaust paths, the closing member is brought into an open state. [Effect of invention]

According to the present invention, the time until drying of the substrate under reduced pressure, that is, the tact time can be shortened.

Hereinafter, referring to the attached drawings, embodiments of the present invention will be described. In addition, in this specification and drawings, the same code|symbol is attached|subjected to the component which has substantially the same functional structure, and the repeated description is abbreviate|omitted. In addition, this invention is not limited by the embodiment shown below.

(First Embodiment) Fig. 1 is a diagram showing the schematic structure of a vacuum drying apparatus according to an embodiment of the present invention; Fig. 1(A) is a schematic cross-sectional view showing the schematic structure of the vacuum drying apparatus; Fig. 1 (B) is a schematic top view showing the outline of the structure in the vacuum drying apparatus. In addition, in FIG.1(B), illustration of the ceiling etc. which are mentioned later is abbreviate|omitted.

The vacuum drying device of this embodiment is a device that dries the solvent in the organic material film coated on the surface of the substrate by the inkjet method under the reduced pressure state. Glass substrates for EL displays. In addition, the solution applied to the substrate to be processed by this device is composed of a solute and a solvent, and the component to be dried under reduced pressure is mainly a solvent. Most of the organic compounds contained in the solvent have a high boiling point, for example, 1,3-dimethyl-2-imidazolidinone (1,3-dimethyl-2-imidazolidinone, boiling point 220°C, melting point 8 ℃), 4-tert-butylanisole (4-tert-Butylanisole, boiling point 222℃, melting point 18℃), Trans-Anethole (Trans-Anethole, boiling point 235℃, melting point 20℃), 1,2- Dimethoxybenzene (1,2-Dimethoxybenzene, boiling point 206.7°C, melting point 22.5°C), 2-Methoxybiphenyl (2-Methoxybiphenyl, boiling point 274°C, melting point 28°C), diphenyl ether (Phenyl Ether, boiling point 258.3 ℃, melting point 28℃), 2-ethoxynaphthalene (2-Ethoxynaphthalene, boiling point 282℃, melting point 35℃), Benzyl Phenyl Ether (boiling point 288℃, melting point 39℃), 2,6- Dimethoxytoluene (2,6-Dimethoxytoluene, boiling point 222°C, melting point 39°C), 2-propoxynaphthalene (2-Propoxynaphthalene, boiling point 305°C, melting point 40°C), 1,2,3-trimethoxy Benzene (1,2,3-Trimethoxybenzene, boiling point 235°C, melting point 45°C), cyclohexylbenzene (boiling point 237.5°C, melting point 5°C), dodecylbenzene (dodecylbenzene, boiling point 288°C, melting point -7°C) ), 1,2,3,4-tetramethylbenzene (1,2,3,4-tetramethylbenzene, boiling point 203°C, melting point 76°C), etc. These high boiling point organic compounds may be mixed in a solution in combination of two or more.

The decompression drying apparatus of the present embodiment, as shown in FIGS. 1(A) and 1(B) , includes a chamber 10, a mounting table 20, and a plurality of exhaust pipes 30, and is connected to the exhaust device P.

The chamber 10 is configured to be airtight, and is formed of a metal material such as stainless steel. The chamber 10 has: a main body part 11 in the shape of a square cylinder; a top plate 12 is mounted on the upper side of the main body part 11 ;

The main body portion 11 is provided with a not-shown import and export port for carrying the substrate W in and out of the chamber 10 . The top plate 12 closes the opening on the upper side of the main body 11.

The bottom plate 13 closes the opening on the lower side of the main body portion 11 , and a mounting table 20 is arranged in the center of the upper side of the bottom plate 13 . In addition, the bottom plate 13 is provided with a plurality of openings 13a and 13b so as to surround the outer periphery of the mounting table 20 . In this example, six openings 13a and 13b are provided along one side of the mounting table 20, and six are provided along the side opposite to the above-mentioned side, for a total of 12 openings. In addition, the exhaust pipes 30 communicate with the openings 13a, respectively.

The mounting table 20 is for mounting the substrate W thereon. The mounting table 20 is provided with lift pins (not shown) for receiving and delivering the substrates W, and the lift pins can be freely moved up and down by a lift mechanism.

A plurality of exhaust pipes 30 are connected to the chamber 10 and the exhaust device P, respectively. The "exhaust path" of the present invention is constituted by the exhaust pipe 30 and the openings 13a and 13b of the bottom plate 13 . In addition, the exhaust path is the one connecting the substrate accommodating space and the exhaust device P in the chamber 10 . In the decompression drying apparatus 1, the inside of the chamber 10 is decompressed by the exhaust device P through the exhaust pipe 30 and the openings 13a and 13b constituting the above-mentioned "exhaust path".

In addition, the exhaust device P is constituted by a vacuum pump, specifically, a turbomolecular pump and a dry pump are connected in series in this order from the upstream side, for example. This exhaust device P is provided for each exhaust path, specifically, one for each of the exhaust pipes 30 .

In addition, the exhaust pipes 30 each have an automatic pressure control valve (APC (Adaptive Pressure Control) valve) 31 as a closing member for closing the exhaust pipe 30 freely. In other words, the APC valve 31 is provided in the portion between the openings 13a and 13b of the exhaust pipe 30 and the exhaust device P. As shown in FIG. In the decompression drying apparatus 1, the degree of opening and closing of the APC valve 31 is adjusted while the exhaust device P is activated, whereby the degree of vacuum/pressure in the chamber 10 during decompression and exhaustion can be controlled, And the drying speed of the substrate W is controlled.

In addition, the decompression drying apparatus 1 is provided with the pressure gauge which is not shown in figure which measures the pressure in the chamber 10. The measurement result of this pressure gauge is input to the APC valve 31 or the control part 40 mentioned later as an electrical signal.

Further, only a part of the plurality of exhaust pipes 30 has a solvent trapping portion 32 downstream of the APC valve 31, and the solvent trapping portion 32 traps the solvent trapped on the substrate W by the inkjet method. The solvent in which the solvent is vaporized. Specifically, the exhaust pipe 30 provided with respect to the opening 13a of the corner portion of the substrate W on the mounting table 20 among the plurality of exhaust pipes 30 is not provided with the solvent trapping portion 32, and the exhaust pipe 30 is not provided with the solvent trapping portion 32 for the exhaust pipe 30 far from the above-mentioned corner. The exhaust pipe 30 provided in the opening 13b of the part is provided with a solvent trapping part 32 .

That is, the plurality of exhaust paths include: an exhaust path with a solvent trap part, downstream of the APC valve 31, a solvent trap part 32 is provided; and an exhaust path without a solvent trap part, not The solvent collection part 32 is provided. In addition, the opening 13a, which is the end on the side of the chamber 10 with the exhaust path with the solvent trapping portion, is farther away from the opening 13b than the opening 13b, which is the end on the exhaust path 10 side without the solvent trapping portion. The corner portion of the wafer W placed on the mounting table 20 in the chamber 10 .

The solvent trapping portion 32 has a mesh plate (not shown), which is a thin plate whose openings are uniformly formed in a lattice shape, so as to allow the gas discharged from the chamber 10 to pass therethrough while trapping the gas. the solvent. The above-mentioned mesh plate is formed of stainless steel or metal materials such as aluminum, copper, and gold, and is formed of expanded metal produced by cold cutting a steel plate, for example. The mesh plate included in the solvent trapping unit 32 may be one sheet, or a plurality of sheets may be laminated. In addition, the mesh plate is formed so that the outer diameter thereof is substantially equal to the inner diameter of the exhaust pipe 30 .

The reduced-pressure drying apparatus 1 having the above-mentioned parts is further provided with the control part 40, the control APC valve 31, and the like. The control unit 40 is, for example, a computer, and has a program storage unit (not shown). In the program storage unit, a program for controlling the vacuum drying process in the vacuum drying apparatus 1 is stored. In addition, the aforementioned program can be recorded on a computer-readable hard disk (HD), a floppy disk (FD), a compact disk (CD), a magneto-optical disk (MO), a memory card, etc. that can be read by a computer, for example. The storage medium may be installed in the control unit 40 from the storage medium. The control unit 40 can also control the exhaust device P.

Next, the vacuum drying process using the vacuum drying apparatus 1 will be described.

(Substrate carrying step) In the vacuum drying process using the vacuum drying apparatus 1, first, the substrate W to which the processing liquid has been applied by the ink jet method is placed on the mounting table 20.

(Substrate drying step) Next, in the state where the dry pump of the exhaust device P is operated, at least the exhaust pipe 30 (hereinafter, the solvent trapping part 32) of the plurality of exhaust pipes 30 is provided. In this example, the APC valve 31 is opened for all the exhaust pipes 30, and the decompression and exhaust of the chamber 10 is started. The decompression and exhaustion by the dry pump is performed until the pressure in the chamber 10 becomes, for example, 10 Pa. After that, the turbomolecular pump of the exhaust device P is actuated to further decompress and exhaust. When the pressure in the chamber 10 becomes lower than the vapor pressure of the solvent in the temperature of the substrate W (0.2 Pa or lower when the temperature of the substrate W is 23° C.) by further decompression and evacuation, the substrate W becomes The evaporation rate of the solvent S increases. In addition, at the time of decompression and exhaust, the gas in the chamber 10 is adiabatically expanded and cooled, and the temperature of the solvent trap portion 32 is lowered by the gas in the chamber 10 cooled in this way. Specifically, when the pressure in the chamber 10 is reduced to 0.2 Pa, the solvent collection part 32 is cooled to 5 to 12°C. The 5~12°C is less than the dew point of the solvent in 0.2Pa, which is 23°C. In addition, the temperature of the solvent trapping part 32 is maintained below the dew point of the solvent S at the pressure in the chamber 10 at each time point until the evaporation of the solvent S on the substrate W is completed. Therefore, since the solvent vaporized from the substrate W is efficiently collected by the solvent collection part 32, the concentration of the gaseous solvent in the chamber 10 is kept low. Therefore, the solvent on the substrate can be quickly removed. In addition, as a method for maintaining the temperature of the solvent trapping portion 32 below the dew point as described above, a method of using a mesh plate of the solvent trapping portion 32 with a smaller heat capacity can be considered. The substrate drying step is performed until the substrate W is dried, for example, until the pressure in the chamber 10 becomes equal to or less than the first predetermined value, or until the second predetermined time elapses from the start of the operation of the turbomolecular pump of the exhaust device P until.

(Chamber drying step) After the substrate drying step, the APC valve 31 is closed for the exhaust pipe 30 with the solvent trapping part, and the exhaust pipe 30 (hereinafter, no solvent) is not provided with the solvent trapping part 32 The exhaust pipe 30) of the trapping part keeps the APC valve 31 in an open state. This chamber drying step is performed, for example, until the solvent in the chamber 10 becomes equal to or less than a predetermined amount, that is, until the pressure in the chamber becomes equal to or less than the second predetermined value, or until the turbomolecular pump from the exhaust device P is activated. Until the second predetermined time elapses. In addition, the second predetermined value or the second predetermined time refers to a value or time for which the solvent remaining in the chamber 10 does not adhere to the substrate W again when the pressure in the chamber 10 is returned to atmospheric pressure.

(Drying step of the solvent trapping part) The drying step of the solvent trapping part is also performed at the same time as the chamber drying step. In the solvent trapping portion drying step, the solvent trapping portion 32 is heated and dried by heat radiation from the side wall of the exhaust pipe 30 or the turbomolecular pump or the like. For example, the temperature of the solvent collection part 32 is increased by the above-mentioned thermal radiation to the dew point of the solvent at the pressure in the exhaust pipe 30 at that point (when the pressure in the exhaust pipe 30 is 0.05Pa, 18~23℃ or above). Therefore, the solvent can be quickly removed/released from the solvent collection part 32, and the solvent collection part 32 can be dried.

(Substrate unloading step) After the chamber drying step and the solvent trapping section drying step are completed, the APC valve 31 is closed for all the exhaust pipes 30, and thereafter, the pressure in the chamber 10 is returned to atmospheric pressure, The substrate W is carried out from the chamber 10 .

After the substrate carrying-out step, the turbomolecular pump of the exhaust device P is stopped, and the steps are sequentially repeated from the substrate carrying-in step.

As described above, in the vacuum drying apparatus 1, only a part of the plurality of exhaust pipes 30 is provided, and the solvent trap 32 is provided downstream of the APC valve 31 . Therefore, the substrate drying step and the chamber drying step can be performed in sequence. In the substrate drying step, the APC valve 31 is opened for the exhaust pipe 30 having the solvent trapping part among the plurality of exhaust pipes 30 . In the chamber drying step, the APC valve 31 is closed for the exhaust pipe 30 with the solvent trap part among the plurality of exhaust pipes 30, and the APC valve is maintained for the exhaust pipe 30 without the solvent trap part 31's open state. Therefore, there are the following effects.

2 is a diagram for explaining the effect of the vacuum drying apparatus 1. The horizontal axis represents the elapsed time from the start of exhausting. Specifically, the pressure in the chamber 10 is at atmospheric pressure, and the APC valve 31 is set to The elapsed time after becoming the open state, and the vertical axis represents the pressure in the chamber 10 .

(Case 1) In the decompression drying apparatus 1, when all the plural exhaust pipes 30 do not have the solvent trapping part 32, even if the APC valve 31 is opened for all the exhaust pipes 30, As shown in FIG. 2 , although the pressure in the chamber 10 is maintained at a high state (about 1 Pa), it gradually decreases until the pressure in the chamber 10 reaches the aforementioned second predetermined value (for example, 0.09 Pa) or less takes 140 seconds or more.

(Case 2) In the decompression drying apparatus 1, when all the plural exhaust pipes 30 have the solvent trapping part 32, even if the APC valve 31 is in the open state for all the exhaust pipes 30, it is also possible to The pressure in the chamber 10 is reduced to about 0.2 Pa more rapidly than in the above-mentioned case 1. However, even when 200 seconds have elapsed, the pressure in the chamber 10 cannot be made equal to or less than the aforementioned second predetermined value (0.09 Pa).

On the other hand, only one part of the plurality of exhaust pipes 30 has the solvent trapping part 32 downstream of the APC valve 31, and the substrate drying step is performed for about 80 seconds, and thereafter, the chamber drying step is performed. The substrate drying step is For all the exhaust pipes 30 including the exhaust pipe 30 of the solvent trapping part, the APC valve 31 is opened, and in the chamber drying step, the APC valve 31 is set to the exhaust pipe 30 including the solvent trapping part. The state is closed, and the open state of the APC valve 31 is maintained for the exhaust pipe 30 without the solvent trapping portion. In this case, at the same speed as in Case 1, the pressure in the chamber 10 can be lowered to 0.2 Pa, and the pressure in the chamber 10 can be made not only the aforementioned second predetermined value or less, but also until it becomes the second predetermined value. 2 It takes only about 85 seconds to reach the predetermined value or less. In the decompression drying step using the decompression drying apparatus 1 as described above, the pressure in the chamber 10 can be rapidly decreased to the above-mentioned second predetermined value or less.

In addition, the vacuum drying apparatus 1 has the following effects. When the substrate W having a square shape in plan view is dried under reduced pressure, the corners of the substrate W are more easily dried than other portions. However, the drying time of the substrate W is preferably uniform within the same substrate. In addition, the portion of the substrate close to the exhaust pipe 30 in which the solvent trapping portion 32 is provided is easier to dry than the portion of the substrate that is far from the exhaust pipe 30 in which the solvent trapping portion 32 is provided. Therefore, in the decompression drying apparatus 1, the solvent trapping portion is provided only in the exhaust pipe 30 provided for the opening 13b of the plurality of exhaust pipes 30 that is far from the corner portion of the substrate W on the mounting table 20 32. Thereby, the in-plane uniformity of the drying time of the substrate W can be improved without making the opening and closing degree of the APC valve 31 different for each exhaust pipe 30 .

FIG. 3 is a diagram showing the structure of the solvent trapping unit 32 in another example of the vacuum drying apparatus 1 . In the aforementioned example, the cooling or heating of the solvent trap 32, that is, heating, is performed by the gas in the chamber 10 cooled by adiabatic expansion during decompression, or by heat radiation from the exhaust pipe 30 or the like.

Alternatively, as shown in FIG. 3 , a plurality of refrigerant pipes 50 may be provided as a temperature variable mechanism for cooling and heating the solvent trapping portion 32, and these refrigerant pipes 50 may be fixed by welding or the like. In the mesh plate 32a that traps the solvent, the cooling medium and the heating medium can be switched to flow, thereby cooling and heating the mesh plate 32a, which is the solvent trapping portion 32. Thereby, the solvent collection part 32 can be cooled and heated more rapidly and appropriately.

In addition, when the temperature variable mechanism is provided in the decompression drying apparatus 1 in this way, it is preferable to cool the solvent collection part 32 by the said temperature variable mechanism in the said board|substrate drying process. Because thereby the time required for the substrate drying step can be shortened. Furthermore, when a temperature variable mechanism is provided, it is preferable to heat the solvent trap portion 32 by the temperature variable mechanism in the solvent trap portion drying step performed simultaneously with the aforementioned chamber drying step. This is because the time required for the drying step of the solvent trapping section can be shortened thereby.

FIG. 4 is a diagram showing the state of the periphery of the exhaust pipe 30 provided with the closing member in order to explain another example of the closing member, and only the cross section of the exhaust pipe 30 is shown. In the aforementioned example, the vacuum drying apparatus 1 has an APC valve 31 whose opening and closing degree can be adjusted as a “closing member”, but as shown in FIG. The baffle 60 of the tube 30 acts as a "closing member". In the example of FIG. 4 , the baffle 60 is attached to the exhaust pipe 30 in a hinged manner. The shutter 60 is controlled by the control unit 40 .

Moreover, in the structure provided with the baffle 60, the decompression speed in the chamber 10 can be controlled by adjusting the number of the exhaust pipes 30 in the open state of the baffle 60. For example, in the configuration with the baffle 60, when it is necessary to reduce the decompression speed in the first half of the substrate drying step and increase it in the second half, first, the exhaust pipe 30 having the solvent trapping portion is kept at a constant pressure. The plate 60 is in the closed state, and the baffle 60 is opened for the exhaust pipe 30 without the solvent trapping portion, and the exhaust pipe 30 with the solvent trapping portion is also opened without reducing the decompression speed. The board 60 is in an open state. Also, for example, in the configuration with the baffles 60, when it is necessary to increase the decompression speed in the first half of the substrate drying step and lower it in the second half, first, for all the exhaust pipes 30, the baffles 60 are made to be In the open state, and after the decompression speed must be reduced, the baffle 60 is kept open only for the exhaust pipe 30 with the solvent trapping part, and the baffle 60 is kept open for the exhaust pipe 30 without the solvent trapping part. Disabled.

FIG. 5 is a diagram showing another example of the bottom plate 13 of the chamber 10 . In the aforementioned example, the bottom plate 13 is provided with a plurality of openings 13a, 13b along one side of the mounting table 20, and the same number is provided along the side opposite to the above-mentioned side. However, the bottom plate 13 is not limited to this example, and as shown in FIG. 5 , the same number may be provided one by one along each side of the mounting table 20 . Furthermore, in the above example, although the number of the openings 13a and 13b provided in the bottom plate 13 is 12, it is sufficient as long as it is plural, and it may be less than 12 or more than 12. In addition, the exhaust pipes 30 communicate with the openings 13a and 13b, respectively.

FIG. 6 is a side view showing another example of the exhaust line of the vacuum drying apparatus 1 , and only the bottom plate 13 of the chamber 10 and the exhaust line are shown. In the aforementioned example, the exhaust line of the vacuum drying device 1 and the exhaust pipe 30 are each connected to one exhaust device P. However, the exhaust line of the vacuum drying apparatus 1 is not limited to this example, and as shown in FIG.

Also in this case, only a part of the plurality of exhaust pipes 30 is provided with the solvent trapping part 32 downstream of the APC valve 31, and the substrate drying step and the chamber drying step are performed in the same manner as described above. From the configuration in which the solvent trapping portion 32 is provided in all of the plurality of exhaust pipes 30 or the configuration in which the solvent trapping portion 32 is not provided in any of the plurality of exhaust pipes 30, the solution in the chamber 10 can be quickly achieved. The solvent is in a state of a small amount, that is, a state in which the pressure in the chamber 10 is sufficiently low.

FIG. 7 is a diagram showing a state of the periphery of the exhaust pipe 30 in order to explain another example of the exhaust line of the vacuum drying apparatus 1 . In the above-mentioned example, although the exhaust pipe 30 of the exhaust line of the vacuum drying apparatus 1 is not provided with any member between the closing member and the solvent trapping part 32, as shown in FIG. A gas supply part 70 may be provided between the closing member (in the illustration, the APC valve 31 ) and the solvent trapping part 32 , and the gas supplying part 70 will promote the vaporization of the solvent trapped by the solvent trapping part 32 The gas is supplied to the exhaust pipe 30 .

When the gas supply unit 70 is provided in this way, in the chamber drying step and the solvent trapping unit drying step, the APC valve 31 is closed to the exhaust pipe 30 having the solvent trapping unit. At this time, it is preferable to start supplying the gas to the gas supply part 70 in conjunction with this, that is, to start supplying the gas to the solvent trapping part 32 . The gas supplied from the gas supply unit 70 is, for example, an inert gas. As long as the supply amount of the gas is such that the pressure around the solvent trapping portion 32 in the exhaust pipe 30 does not exceed the vapor pressure of the solvent trapped in the solvent trapping portion 32, the solvent can be trapped efficiently. Section 32 is dry.

(Other Modifications) In the above example, in the case of decompression and exhaust in the chamber 10 in the substrate drying step, all the exhaust pipes 30 are made to open the APC valve 31. However, in the substrate drying step, the APC valve 31 may be opened only for the exhaust pipe 30 having the solvent collection part among the plurality of exhaust pipes 30 . In this case, after the pressure in the chamber 10 becomes lower than a predetermined value, that is, after the drying of the substrate W has progressed to a certain extent, all the APC valves 31 may be opened. The APC valve 31 is opened only for the exhaust pipe 30 having the solvent trapping part among the plurality of exhaust pipes 30, whereby the substrate W can be dried more uniformly depending on the solvent. In this case, the time required for drying the substrate W is longer than when all the exhaust pipes 30 are opened from the beginning, but after drying the substrate W to a certain extent, all the APCs By opening the valve 31, the substrate W can be uniformly dried and the substrate W can be dried in a short time.

In the above example, the carrying out step of the substrate is performed after the solvent trapping part drying step is completed. However, as long as the exhaust pipes 30 are each provided with one exhaust device P, when the time required for the solvent trapping section drying step is longer than the time required for the chamber drying step, the Before the drying step of the solvent collection part is completed, the carrying-out step of the substrate or the carrying-in step of the next substrate is performed.

In addition, in the above example, the closing member such as the APC valve 31 is provided in the exhaust pipe 30, but it may be provided in the exhaust path as long as it is provided in the openings 13a and 13b, for example. , the openings 13a and 13b can also be closed on the upper surface of the bottom plate 13 . Similarly, the solvent trapping portion 32 may be provided in the opening 13b instead of the exhaust pipe 30 as long as it is located downstream of the above-mentioned closing member. [Industrial Availability]

The present invention is useful in a technique of drying under reduced pressure on a substrate coated with a solution by an inkjet method.

1‧‧‧Decompression drying device 10‧‧‧Processing container 11‧‧‧Main body 12‧‧‧Top plate 13‧‧‧Bottom plate 13a, 13b‧‧‧Opening 20‧‧‧Plating table 30‧‧‧Exhaust pipe 31‧‧‧Valve 32‧‧‧Solvent collection part 32a‧‧‧Mesh plate 40‧‧‧Control part 50‧‧‧Refrigerant pipe 60‧‧‧Baffle plate

[ Fig. 1] Fig. 1 is a diagram showing a schematic configuration of a vacuum drying apparatus according to an embodiment of the present invention. [Fig. 2] A diagram illustrating the effect of the vacuum drying apparatus of Fig. 1. [Fig. [Fig. 3] A diagram showing the structure of the solvent trapping section in another example of the vacuum drying apparatus. [Fig. 4] A diagram showing the state of the periphery of the exhaust pipe provided with the closing member of another example. [Fig. 5] A diagram showing another example of the bottom plate of the chamber. [Fig. 6] A side view showing another example of the exhaust line of the vacuum drying apparatus. [Fig. 7] An explanatory diagram showing another example of the exhaust line of the vacuum drying apparatus.

1: Decompression drying device

10: Handling the container

11: Main body

12: Top plate

13: Bottom plate

13a: Opening

13b: Opening

20: Mounting table

30: Exhaust pipe

31: Valve

32: Solvent capture section

40: Control Department

P: Exhaust

W: substrate

Claims (7)

A vacuum drying device for drying a solvent in an organic material film coated on a surface of a substrate under reduced pressure, the vacuum drying device is characterized by comprising: a chamber for accommodating the substrate; and A plurality of exhaust passages connect the space in the chamber with an exhaust device for exhausting the inside of the chamber, the plurality of exhaust passages are respectively provided with a closing member that can open and close the exhaust passage, and the plurality of exhaust passages are respectively provided. The exhaust path includes: an exhaust path having a solvent trapping part, downstream of the closing member, a solvent trapping part for trapping the solvent in the solution vaporized from the substrate is provided; and a solventless trapping part The exhaust path of the part is not provided with the solvent collection part, and the end part of the exhaust path with the solvent collection part on the side of the chamber is compared with the cavity of the exhaust path without the solvent collection part. The end portion on the side of the chamber is further away from the corner portion of the substrate housed in the chamber. The vacuum drying apparatus according to claim 1, further comprising: a temperature variable mechanism, and cooling and/or heating the solvent trapping part. The vacuum drying apparatus according to claim 1, wherein a gas supply is provided between the solvent trapping part and the closing member. The supplying portion, the gas supplying portion, supplies a gas that promotes vaporization of the solvent captured by the solvent capturing portion. A method of drying under reduced pressure, using a drying device under reduced pressure, the drying device under reduced pressure is used to dry a solvent in an organic material film coated on the surface of a substrate, the drying method under reduced pressure, wherein It is characterized in that the decompression drying device includes: a chamber for accommodating the substrate; and a plurality of exhaust paths connecting the space in the chamber and an exhaust device for exhausting the chamber, and the plurality of rows Each of the air passages has a closing member that can open and close the exhaust passage. The plurality of exhaust passages include an exhaust passage having a solvent trapping portion, and a trapping member is provided downstream of the closing member. The solvent trapping part of the solvent in the solution vaporized from the substrate; and the exhaust path without the solvent trapping part, without the solvent trapping part, the vacuum drying method comprises: a substrate drying step, For at least one of the plurality of exhaust paths including the solvent trapping portion, the closing member is opened; and in the chamber drying step, after the substrate drying step, for the plurality of exhaust paths For the exhaust path with the solvent trapping part, the closing member is in a closed state, and for the exhaust path without the solvent trapping part, the closing member is opened in an open state, and the substrate drying step includes cooling the Steps in the solvent trapping section. The drying method under reduced pressure of claim 4, wherein the chamber drying step includes a step of heating the solvent trapping portion. The vacuum drying method according to claim 4, wherein the chamber drying step includes a step of supplying a gas from a gas supply unit provided between the closing member and the solvent trapping unit. A gas that promotes the vaporization of the solvent captured by the solvent capture unit. The drying method under reduced pressure according to claim 4, wherein the end of the exhaust path with the solvent trapping portion on the side of the chamber is smaller than the cavity of the exhaust path without the solvent trapping portion. The end of the chamber side is further away from the corner of the substrate accommodated in the chamber, and the substrate drying step preferably includes the following steps: for the solvent trapping in the plurality of exhaust paths The said closing member is made into the open state of the exhaust passage of the part, and thereafter, the said closing member is made into the open state for all the said plural exhaust passages.

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